For ChIP-seq, cells were fixed with 2mM DSG and 1% formaldehyde, and samples from sonicated nuclear fraction were incubated with each antibody and histone-DNA complexes were isolated. ChIP-seq libraries were prepared using NEBNext ChIP-Seq Library Preparation Set for Illumina (New England Biolabs) following the manufacturer's protocol.Libraries for RNA-seq were prepared using the TruSeq Stranded mRNA Sample Prep Kit (Illumina).